When a semiconductor storage medium, such as a NAND flash memory, is used to form a storage device, a transfer process (a compaction process or a garbage collection process) is performed.
In the semiconductor storage medium, such as a NAND flash memory, data is input and output in the unit of pages associated with an internal memory cell group. In the semiconductor storage medium, in order to complete the writing of data to the memory cell group, it is necessary to perform a plurality of writing stages, the order in which data is written to the memory cell group in each writing stage is defined, or the association of data required in each writing stage is defined.
In order to achieve the transfer process in the semiconductor storage medium, necessary data needs to be prepared at an appropriate timing and a reading and writing process needs to be performed for the semiconductor storage medium in an appropriate order.